I realized you might have come up with this list after looking around on the wiki already but the hydra, cerberus, phoenix, archangel and queen bee have all had someone try their hand at creating such a monster within the past few weeks.
From your list, I'm most interested in the hydra and pegasus.
I'd also like to see another lighting element monster, the raiju and thunderbird are ok, but something like a lightning elemental would be nice
the bee exists, but the queen subspecies does not have a profile just yet. But it is not like the ants, because in the ants, it is understood that it is the same monster with different ranks, so much so that a normal ant can become queen. The profile of the bees, on the other hand, implied that they are different monsters.